It may also be worth remembering that the coding properties of a codon
need not be absolute. Accuracy of translation is not perfect, and the
existence of natural suppressor tRNAs results in so-called termination
codons being used for termination some of the time, and for encoding
various amino acids the rest of the time. One might therefore envisage
scenarios in which the genetic code can change in a continuous manner rather
than a strictly saltatory one. I would be surprised if this had not
been discussed before, although I don't recall having seen it.
gg
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* George A. Gutman *
* Department of Microbiology Tel:(714)824-6593 *
* and Molecular Genetics FAX:(714)824-8598 *
* University of California INTERNET: GAGUTMAN at UCI.EDU *
* Irvine CA 92717 *
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